Can cable faults ever go away?

Telcos have stepped up measures in recent years to improve redundancy and re-routing efforts during cable disruptions, but costs and nature still stand in the way.
Written by Vivian Yeo, Contributor on

Telcos in Asia have stepped up investments over the last few years to enhance redundancy, cable routes and re-routing efforts, but the region is still not safe from cable disruptions.

Users located in the Asia-Pacific region were subjected to slow connections speeds to sites hosted outside of the region on Aug. 12 due to a fault in the APCN2 (Asia-Pacific Cable Network 2) undersea submarine cable. Telcos have pinned the fault to Typhoon Morakot, which struck China and Taiwan around that time.

Such disruptions are not new. In 2006, APCN2 was damaged by seismic activity, when an earthquake measuring 7.1 on the Richter scale occurred off the southern coast of Taiwan. Early last year,undersea cables in the Mediterranean Sea suffered multiple cuts, crippling voice and data communications in the Middle East and South Asia.

APCN2 Segment 7 repair ongoing

Segment 7 of the APCN2 damaged by the recent Typhoon Morakot is currently undergoing repairs, and is expected to be restored within a week.
According to Mark Chong, SingTel's executive vice president of networks, the Asean Restorer cable ship is currently carrying out repairs to segment 7 of the APCN2. SingTel is part of the consortium that owns APCN2.
"The repair is targeted to be completed by the end of this month," he said in an e-mail. "The APCN2 Segment 1 was repaired on Aug. 14, which restored traffic to most destinations on the cable."

StarHub, another investor in APCN2, said even as repair work is ongoing, Internet connectivity had "normalized" the same week the damage was discovered.

Learning from the past
Industry stakeholders say progress has been made by telcos over the last few years in terms of redundancy and re-routing processes. On the other hand, any network downtime or lag is increasingly a source of irritation.

Matt Walker, principal analyst at Ovum, noted in a commentary earlier this month, projects such as the Transpacific Express and Asia America Gateway (AAG) have contributed to Asia's international network connectivity. "The region's cable systems are now much more meshed and resilient, and less prone to catastrophic failures", he pointed out.

"Redundancy is nothing new in undersea networks, but what's different is the number of alternate or backup paths now available in the event of a single failure," Walker explained in a follow-up e-mail interview. "Additionally, the rerouting process is much more automated now thanks to new technology such as optical switches and other devices."

Simon Cooper, vice president of network strategy, architecture and optimization at Tata Communications, pointed out that the "massive number of cable breaks" in the latest incident could have been a lot worse.

"Given the sheer number of cable breaks--for instance off Hong Kong--it [was] a testament to the industry that a near-normal service [was in operation]," he said in an e-mail.

Some users, he acknowledged, had still experienced slow Internet connectivity some 48 hours after the cable cuts were reported, but this was because of the multiple breaks and limited number of routes that had remained in service. "It [was] simply not possible to fully replace all that cable capacity until at least some of the repairs had occurred."

Michael Sim, StarHub's senior manager for corporate communications, said in an e-mail, the telco has, since the 2006 incident, acquired additional bandwidth capacity to expand and enhance its international connectivity, and to provide diversity to the existing submarine cable systems. One such investment is in the AAG.

"From StarHub's perspective, we want to ensure that we have additional bandwidth capacity on all the major cable systems, and a diversity of cables and alternate routes. Our involvement in AAG is part of this initiative to boost the resiliency of StarHub's international connectivity."

SingTel's executive vice president of networks Mark Chong, said the carrier increased its connectivity westward to Europe, and spread east-bound traffic onto more submarine cable systems.

Chong added: "We are currently building the new cable--Unity--from North Asia to the United States. We are therefore able to enjoy, and offer to our corporate customers, cable diversity which allows us to divert traffic from one cable system to another should the need arise."

According to Tata's Cooper, routing cable systems to avoid disaster-prone areas could alleviate some concerns of cable disruptions due to natural phenomena. The company's new TGN-Intra Asia cable system had been laid "with a specific view to avoiding the quake zone around Taiwan--by routing to the very south of the Luzon Straits".

Yet, "nowhere is completely safe from natural disasters", he noted.

"The only way to ensure that disruption is minimized in a disaster scenario is to plan and evaluate your network needs under various scenarios--whether it's a sub-sea earthquake or a [voltage drop in an electrical supply] in a particular city area--and to try to invest in a network that will have affordable survivability in those potential situations."

Major disruptions can bring important lessons but at the end of the day, practicality rules, said Ovum's Walker.

"The fact that both the December 2006 and August 2009 breaks were in the same general location--around Taiwan--will likely cause operators to look more closely at cable placement issues around Taiwan [and] the possibility for other landing points, et cetera," he noted. "But in reality all of these things are very expensive, and when the public hoopla around this dies down in a few weeks, there is a good chance things will go back to business as usual."

Editorial standards